aurora borealisauroral absorptionauroral capsauroral electrojetauroral formauroral frequencyauroral isochasmauroral lightauroral ovalauroral polesauroral regionauroral stormauroral substormauroral zoneauroral zone blackoutausteraustral axis poleautmatic rain gaugrautobarotropicautocadautocovarianceautogenetic topographyautomatic delineation of watershedautomatic weather stationautumnal equinoxauxiliary thermometerauziliary spillwayavailable eater capacityavailable moisture capacityavailable wateravailable water contentavalancheavalanchingaverageaverage annual floodaverage ground water velocityaverage lifeaverage stream flowaverage velocityaverage yearaveragingavilability ratioavulsionaweatheraxial strwamaxial velocityazimuthal dialazonal soilsazors high
